atherosclerosis ath·er·o·scle·ro·sis (āth'ə-rō-sklə-rō'sĭs)n. A form of arteriosclerosis characterized by the deposition of atheromatous plaques containing cholesterol and lipids on the innermost layer of the walls of large and medium-sized arteries.

A form of arteriosclerosis characterized by the deposition of plaques containing cholesterol and lipids on the innermost layer of the walls of large- and medium-sized arteries. Individuals with atherosclerosis have a higher risk of coronary artery disease and stroke. Smoking, high blood pressure, diabetes mellitus, and elevated levels of fat in the blood contribute to the development of atherosclerosis.